Board Thread:Pokémon Help/@comment-32671610-20170724151324/@comment-30804097-20170724171732

First of all, never use 3 megas at the same time. I hope you already know this, but you can only perform Mega Evolution once per battle.

Rotom should have Thunderbolt instead of Electro Ball, Will o' Wisp instead of Omnious Wind, and Volt Switch instead of Substitute. All of these are TMs.

Blaziken seems good, though I prefer Blaze Kick over Flare Blitz so Blaziken can actually sweep without getting recoil damage.

Aegislash is fine, though Sacred Sword or Iron Head is prefered over Aerial Ace and Night Slash. Swords Dance is also an option.

Sableye and Diancie are fine.

Shaymin-S should have Energy Ball instead of Worry Seed and Dazzling Gleam could be used instead of Leech Seed or Synthesis.